Equine influenza occurs sporadically in Europe, Japan, North America and South America with recent outbreaks in the United Kingdom.
Australia had a significant outbreak of equine influenza in August 2007, which was successfully eradicated.
Horses, donkeys and mules are the natural host of the virus that causes equine influenza.
How equine influenza spreads
Contact between horses is the main way the disease spreads. However, contaminated equipment (such as horse transport equipment) can spread the infection as the virus can survive in the environment for up to 36 hours or longer. People can also spread the infection because the virus can contaminate clothing and skin.
If an outbreak occurs, a high number of exposed horses will usually get sick because the virus is highly contagious.
Signs of equine influenza
- fever (up to 41°C) after an incubation period of 1–5 days
- frequent dry hacking cough during the first few days
- then less frequent and more moist coughing which stops after 1–3 weeks if horses are well and rested
- nasal discharge, changing from clear to a thick mucous
- fatigue, lethargy and loss of appetite
- foals die from pneumonia if they have not had adequate colostrum
- death of older or weak horses, more susceptible to secondary bacterial bronchitis.